SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19feafcaa51c571ac3aee06cf1c6fc92427d08d436dc82c63617adadbfa52e2a' 
  AND token = 'tVUOkZGjtYS+jZWVugVxNkTFX/dfXEXFkTEhP2f8dAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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