SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b13ac12a19fbca4bd3eab29c671eeabb3d113b0886bcaef1af09ec5eff18e7f' 
  AND token = 'MbvpXd2rZdHIsmRY5VHi1GWIlYPXANGdsaKXsQubKQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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