SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9242e78cdca798b4b670487ce653fd59c3f1c4b981503a19e015e8204a1c9f66' 
  AND token = 'i3ASJe7A5TdUSYepBTKygB44QW+A/vhn4ZeTb4JOkA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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