SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a87143e431e842159eacaa43979d1de79de46c5f4ee8f111e87856c407c1714' 
  AND token = 'KaR1Aq0jx66OZ/PVyQqJTuOTRCWfPcGL/1AvFXDtX5g=' 
  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"
    }
  }
}