SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c066b8f3d765b8bddbfac3d7560161b1974d400360fad6a86c2fc7204bbec43d' 
  AND token = 'XsQ1yfE+d+h6qMrGOIQI1FrzBBXvkKCR8+tnXycSw70=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00094

JSON explain

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