SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b149cc56067661c95f062171b7a5d9dd1a7b17aaea7e7f2ef224041d6321275c' 
  AND token = 'LhaO0q3A5Duo3/+KXUafsNyPPgdByG5eFQQVDcfawD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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