SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf189447d755467f24f32b271994c96335551273008cd861ca88e5aa3727bf20' 
  AND token = 'PufycPJRHa+z35M6jylHsjjL1Rr+jcU80ZOH7mU7G+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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