SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a17facd91e8f4d6e4779c125ed4a9edd308d4bf8dccd0fde84914fac71aacd5' 
  AND token = 'hnCCR4VmV6WbqgCjkYrpb8uSouTmSScX98QEYdQq7qk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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