SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11275289319d2671de4762bebaa956edec37cf993cd7bd097dcd3bd783b45d55' 
  AND token = 'szQIRLRbkQkspE8INxdCvsDpxmri0hwOyazBkkS1UvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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