SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b1e930c78eefba941891ddb2fa308034c2ab7ebfbebb8cb3b9427347a7e2e61' 
  AND token = 'CQ1dkMul3M+HVabgx/Ck09V1PHAoJfPQytZkNyOmuQo=' 
  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"
    }
  }
}