SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bbbe7767e5f1a426a020a1b8576c79ee5058193351394c65e06757e6dc1db1c' 
  AND token = 'f+QK5BNF44gpYUjFo8lR9TCAWZb7BiwkmLNbXyNla74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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