SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b8e1c25e1341d300754f469b945a41d54ecc0f94f6c39156fc4191bc10f8eb48' 
  AND token = '2Dk87pXg2oP1uI4AUZbVDjUBuzkuSiDYJj2QhI7/09A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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