SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '060fc96d42c27fbe3550eaf3b26aa6f929d0da8463666b990d083ce009dddfba' 
  AND token = 'S0Np9uPXmPG2jqq5liUH0RRdg7gZyjF51A8992o10Ig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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