SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4274f4d924f4bf1dd23b41aa99af24f4fbadb1301171fadc65c90a97c86a51b6' 
  AND token = 'S1hvJybW3V67CMH/EH0QD9iDLq3NKGCUyyarUwbaVes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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