SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '682431bbc9e0fe8d1904fac88b9b20e5b2f25c02757551cc76a93034bcd20234' 
  AND token = 'E3koc0xZ76YZpqn8PQnIAZy2UT35iZitSgNDzVWArro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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