SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd69a073506d69483336d3f0152c78df15624551dbea25f112565d449a1125a92' 
  AND token = 'oNDRVBpVmmowfo/+yXbmvASqcwYTbrpgPWncw4vnGTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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