SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75872e7e602ad5eae792e48a7b12e9b252ebb136180237ad9ae51a2606e2c3b5' 
  AND token = 'azujNCydArzlbeM3RxFMuSvBNNzvnjgaBr1U3btJTMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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