SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ecb71e26827832e8f2fdf477616c64f6cb99acd350e3bbebd385157070da52d' 
  AND token = 'jXZ9N8ixNvDCdQyGIiT1+/KO5ASJGk+RssPbBrLCDS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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