SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33b2dd60ef04483a5e8b3364048a1ee1586121975ecacfc7a39b1a5457222ab6' 
  AND token = 'RrmTQMiq7pY/s8/JrBadtvtMypXrnOSb71lAerafKF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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