SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb6168f38df99e04a64977502db5f67f1928b7dea883a0e5b9cabba8967d8185' 
  AND token = 'uqW7DJ9mkHEVNezLiPOgK58CswF+EeU7x1dW3ZXhBB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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