SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ad7523da88f86210ac3737bd252e57277689a5b29952757f71685ffd0194fe2a' 
  AND token = '7d6fouZXFQsVnINVEgT7VW3p4eH80gdJBJUq96g+PMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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