SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '03e2a1bc0dfc9e1389c3b734a9bfeefb2b0819660fa4678021f4d9a6d2df8931' 
  AND token = 'mK7ghMUEawdZotK3e82yatl1ZjY7Wgxqc+y3atqdqSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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