SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7664795547d429978f9f47fb35622ac5c7a4695f58d3cf65640064ea98eda02c' 
  AND token = 'B9uL66dCIUO2RNz1emquqqh0hIEeEUqaqT2Eyb85lMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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