SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd882184d10c0d130f5507a997100ff2728cb6a59938db65f8cff4294cbf95c9' 
  AND token = '4EzDFDOPqfDC3z4+bCllIEWSFt5t2fqHrylhDez75Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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