SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd27bfab104f363f1d34b76a2280efca2e3d2bf1141a0dce874f651178becce0' 
  AND token = 'dzF+OjH6B5fdtfrYCJ0UoZQYZ/R7L49JmIICk5bHDzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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