SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b70affd47cb26f06869d335349ce6a1cc38e773e1315a582babcb0f230648c99' 
  AND token = 'TB7NA9q1guO54fXrJIGZKHfBfa/Ax8uuluXlP0jGSnQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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