SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab0757bfc1d448e7c5089cfd4735ffa9ab770b080c2a85a2643ebdd946ad6059' 
  AND token = 'Odn8jsrBIK3LgwYBP9qRe2Ngq8kjdXCqQJDZLdvexQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}