SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7eb60c816198de2616b08f104221c587800b0d4d0b84f72316a0a3a350088d7a' 
  AND token = 'Si8Ym7GM18FCOypUuFgCF/YsrnOR7F17PBd8AN8lkVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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