SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9bc51973182134f27644e7bf4f5297a93d566075b1f5c07bb27f4547ab479ad4' 
  AND token = 'g/OP2MBvoOB2tQswbqxKIJhB3739ubbgZpPV/EnGGXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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