SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2de3bd513efdd7d1a160652e3bdbbfb84a78ff3ab23bd15f820c151c625c0e83' 
  AND token = '+BkvzqODDP0dXdoLIFbx1YXfi0YTPK5XTU+9Gl1DjkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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