SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cf06f0a078dfcd355b1471eeb39b6b6411af10586a5c90d461c0d5b44de7889' 
  AND token = 'WScOs2M48hasaAhjRc/sNVAdo5QQ6K3Nh1GI1kiYhwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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