SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95e7226ef5ca6aeeabf1a24502e542892ce83f184eff1c16713565c914e3f591' 
  AND token = 'kxOTaUbEQN1a/8NtZ2AqrTyfmC+hbiEpakbl7reGGAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}