SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb6d2704c696bf1a6b66c6c5af2b794288c496440d2007e5f90a6a63eb6df900' 
  AND token = 'xhZkKAk7WWkNZwvT04lIN6Q97YJoKbU4PS4QaLs+cw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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