SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9620b61410189fb4caf76da2708ec79d69bdaae89a7a5f92503eadfa277f5ecf' 
  AND token = 'YJzav9zMhxZzqIQIq3kkXoCF60olKOS/YepnCw03h9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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