SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '56c0b33e104f71b4fb853e0410a925a386a5bc2fac99a5ed20dbc09fd679f3f1' 
  AND token = 'oFgtr1I3LnW3zWWFMWyQXIrzluXSBDVoBVB0h/1ok1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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