SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '983b682c16ba48e257e774b3cca3d25cc3f52bb04bc8cc0c33a09029a544ed46' 
  AND token = 'A52q44UYvZgU2fygWF078BqzjNK2HTxe8P0BFXGNw74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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