SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e95886fa5d040227687c05bb847ec78070e8613d2c6399b2fd4751f79202189c' 
  AND token = '5r4KyK1DjJXBdCU36SdsPsIvqe0wPVZXHP9aOUewNqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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