SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '813d56503e888a650fc1ebb46e5c1642a0955bd85646534d8c6d04d174045b7a' 
  AND token = '7tgJ50cGHJJI/4sQEQqXbeLXu8e9gEc8O7TVl2iZkX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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