SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea02ccec73512b8475b4204f8c4af25216ab6f8fcc7a6a4cc57a3457702d9a43' 
  AND token = 'PjonLiSNscBenHCZic95JjOVwG3a4UyDTEg5g2H+3LU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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