SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '269822d02475ba3cea75443af9ecb34ed5496f8b60149b5338eea06b82407241' 
  AND token = 'upjmzy/svfUVEmFtsjui4ZP2SE3jJm7Fl/vYsnnA82g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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