SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1316f088c698ab0544ed8d7fd7ce32e88755009b952f245616d4ae5c2eb0c473' 
  AND token = '0IBD2CxYS3+tVID+8XrgKNWWKPA3uKakhIFAoqm6LAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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