SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f9f329587196fe223ff15a5225d6aba71c96a10da036d75c6d384aae7f9c4dc' 
  AND token = 'hRO0PHwqJk8RF/rCGGAOSEjz7JZRV0v2W0uybYB5cbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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