SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7d57bc20d5c3a12c794881ae67fbf1bb75b51519f3dab820cb18f5eb3a24a45e' 
  AND token = 'nsveDqVcdf1AM1W3EPkIy/Xic6iCOZYd1NJntjCjWBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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