SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fd5caf844161ac17c6918f56dc3cd489d0565f6077499450920f6fc496075b3' 
  AND token = 'tjjJdu9i0WWSUmO0kQC9ymkpZyNY+oh+/NJ/vLf6LVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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