SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d48636f2ee148e31c0614225d7dd015776bc2111cd30f6ad99e1650f6f822ed' 
  AND token = 'MmZ8q0Aoq/wUiX55S95PNQPEFXDZ1nOmLRPmxRINQrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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