SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63571b08a61c5e389657e8803636af1ebd9fdcb2f49436fcb0b57121485ac90d' 
  AND token = 'IK8KEGqiM1Q2mPVASNCu6/OE2vsDm5wQ8DalVWJB0Z8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}