SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '37be05872b8da96ff519488a9de371308ff3f27d25d628cab2a0d7a2c76a3387' 
  AND token = 'ZsI3CFqqKrjmPtl4TK2k+VaTiE0+il23plUrhS/TYgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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