SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f964434f8afbae01f41f76fabeec09650e37604a85ca924fe5b25362ebbed3d6' 
  AND token = 'StJ0CVW2U927cuk1ADr4iq1NMkvnxVMTcxF1LqoMmik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}