SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97e95b2c88a24ac7b0f2bbc93c53ab74ff94e78cfcb43f06e149c2364070dbdd' 
  AND token = 'zR2k2Ajl4sOvbjtYhWFdu5Yg/GURkulPLHzvMsfT+zA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00264

JSON explain

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