SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20d54ed978d761ca6c56687f9f0f7ca062dadc9535606dfbfc9e8d3e4481faa5' 
  AND token = 'E3r0Q5DPGF0CykSxRcNHebYO0fw1qbr95no4yDQql6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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