SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '302f0320d17225f8d0422f7c56b63d2246cb79884a0db1906e400690bf5514fe' 
  AND token = '8pLbetoXrvYDOLA3SnqHnPsZ9zpIHZTFNK60Uo2VWbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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