SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4734121550e0cc4fad9cc9678e2e3d82380c4e769911943d614a31320ef34190' 
  AND token = 'YDP8yBYJpybnG2TTJQ9FyNp3VilIpZ1YNTEWzovnmPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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