SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1246f76e659115f3af82b605c89a56ad09e2cadcb980a67df44865f3a3a062ad' 
  AND token = '0noOQQz6wE2iac6MfIrFAicoHnbhaUDot3Km4YeX0XY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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