SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d5d3f31370e8e924de482c33fdd818e6fa626d3fa5fa5eb474292528d199669' 
  AND token = 'XVwZZfwjf5NmYbDriudj9rKANGYYOPBTTCKSH1WWeVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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