SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee5734fb0baf3f5d1a138897a583e7552d2f1e92c218571ca9e278970e9442b4' 
  AND token = 'NzA+7Zq2UQa/Fsjzp9uL+pohxQXlvkiTlYx05NWUhI4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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