SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4d6141e819e3a5ca6e79514ab10d3b9e32b983bd5d4e3f0a5d4b27715e5b602' 
  AND token = 'mmEnp9w/0gEnLD963d/qL5jkofCSouD76uGyUVaPJ0M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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