SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cec0cf11f9530df4577db5daabba3ee21d7558ba57d33302e3c181ca882ab8e' 
  AND token = 'es542W1EkpmyzcxpTezADmgDPd2zEU386j6ZrgPmGpI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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